In finding a solution for myself, i have stumbled over some new 12v technology!

*note: I am well aware there are other voltages for inverters than 12v but it does make theft undesirable.

If you travel in caravan or live in a houseboat are retired and thinking of travelling around in one for a year, these may be what to get but the catch as usual is do all the paper-work(electronic) for import yourself.

There is a battery called a LiFePO4, i had seen ads for them previously and inquired but the "purpose and price" was not inside anything i had been looking for.
This is what was odd!!! Recently i saw an ad that "touted" a 12v 40ah to be a "deep cycle" and 2000 discharges to 100% or 10 year life span.
I decided to inquire because its size was so small to see how it stacked up against a lead acid for price against use.
Here is what i found.
Effectively, the battery device system can be custom set up to be a particular size up to 1000ah at 12v (e.g. 500ah) as a single unit or set battery but you cannot add or subtract from it.
What it can also do unlike lead acid type or normal deep cycles is output at 12v 420 amps constant , meaning 5Kw constant output.

4 x 250ah lead acid batteries cost $2000 approximately and will only give a maximum safe discharge of 2Kw absolute maximum at 12v.
This is because a single lead acid 12v deep cycle at maximum can only output safely 500w(40.1 amp 12v).
AND only an absolute safe maximum of 4 lead acid cell type batteries can be placed in parallel.
So you would only get 4 lead acids with a 12v system.
You would also only get around 1 - 2 years use precariously.
4 x lead acid 250ah would cost approx. $2000-2500

A 500ah system self imported would probably cost $3000 by the time it reached your home.

Not a perfect replacement idea but getting on for it in every detail!

note: How to DIY import can all be found here...
wild-canidae-conservation-forum.netne.net/austhouse15kw.html#stephy

Here's the topic proof...
optimum-china.en.alibaba.com/product/1520294427-200128904/Deep_cycle_12V_40AH_Lithium_iron_phosphate_Battery_high_quality_for_solar_street_light_caravan_golf_cart_UPS.html?edm_src=sys&edm_type=fdbk&edm_grp=0&edm_cta=read_msg&edm_time=realtime&edm_ver=e

Interestingly, i have seen many years back a hot water system in a caravan.(presently, Dux has a mains plug-in 50L model with a 1.6 Kw element)

Dezman said..
Washing machine and heavy tools etc. a small gen will cover that and really one or two hours a week would cover it. Cheap power for a bit of fuel.

Really!...gosh....it wouldn't for me and many others

I was thinking two washing loads a week, however I'm single :D.

Your male like us ? what washing.

Anyhow, as for 2000 for a setup, THIS IS A SMALL SYSTEM
My system is wind 400-600max 3 phase AC 12v $300
2500w 12v pure sine wave $400
3 panels 80w 12v $300
4 x 40ah lead acid sealed $420
20 meters copper 6mm2 - x 5pieces (100 meters total) $120 - lucky! some were on special
programmable hybrid charge controller MPPT 12v/24v $190
electric cable joiners $60
50 amp 12v solar controller $50
-
(requiring 2 x 6.5 meter lengths of NB 40 med extra pipe (50mm outer diameter)) $120
6 x guy wire cables - estimated from some sources $180.
staking pins maybe another $40
TOTAL, $2180

Only problem is it does very little.
I need a reasonable microwave, reasonable time for tv and computer and some cooking after dark and lights.
Then there is refrigeration which i see for energy efficient does not take much.

Washing machine and heavy tools etc. a small gen will cover that and really one or two hours a week would cover it. Cheap power for a bit of fuel.

Everyone has thought of those small econo generators from ebay, fuji makes one around 4-5Kva , but they stack up expensive for fuel compared.

Gas is like electricity to me, it will just suddenly race up in price.

Microwave! Buy a real steak from the butcher instead of a microwave dinner.

Some microwaves have a microwave and grill combine function and a separate grill function.
It's for real steak!

To be clearer on the 12v problem!
If you discharge a lead acid deep cycle (the only cheap battery) beyond 30% (lower than 70% full) the charger cannot charge directly. It must charge for a period and then go dormant for an hour.
So it is never a good idea to overrun that top 30% "float charge (CONSTANT CHARGE)" or you cannot supply with your panels because the charger is switched off(stage charging system).
So now its deep cycling and you have only 250 - 320 occurrences of what your doing if you exceed that 30%(better than that really but rule of thumb).
Also, lead acid require maintenance of equalising.

So if you had to use a lot because your treating yourself in a caravan or just life, your not doing too good with four 250ah.
They will only last a year and deliver little at 12v.

These i found will go at least four years and can be loaded much heavier for longer.
And cheaper in the long marathon run compared.

Nice setup and nearly the same size I use, 200 watts.
I use an iPad which are great on power same as a tablet.
My TV is 3 amps but only on less than 2 hours a day.
I would of thought the fridge is a high user of power!
Still can't understand why people love microwaves!
As for a genny I can't stand the noise being a sailor so
It's turned off as soon as job is done. Refuels are so far apart
I can't remember doing them.
I think technology is amazing and feel very lucky to have it,
I guess some people expect a lot from it for little money.
In Australia we are so far from reality with our over sized lifestyle
Of big cars, houses and etc.
I'm not one to go without, however there is some satisfaction in
Being self reliant.

am selling my small stand alone system at moment [adelaide area]

2x mated BP solar modules 250/2f in adjustable frame on vertical pole

+ distributor board, 12v deep cycle battery [optional] $800. [PM ME]

suitable for houseboat, house, caravan, or agriculture usage

peak flow 50w x 2 =100w, peak voltage 17volt, peak power current 2.94A x 2 =5.88A

have found it enough for me over years for led lights, fridge, radio, recharge, computer.

cooking with gas, washing at laundromat, or plastic garbage bin when moving..... life's good